We have reduced support for legacy browsers.

What does this mean for me? You will always be able to play your favorite games on Kongregate. However, certain site features may suddenly stop working and leave you with a severely degraded experience.

What should I do? We strongly urge all our users to upgrade to modern browsers for a better experience and improved security.

From what I have heard, Kongregate is trustable. I have given them my email address, and I have never received any spam. I would trust my payment details with them, I just have no games to upload so I havent before.
Overall though, I have never heard of 1 complaint against them.

Just to be clear, if you’re going to upload any games to the site they have to be games which you have created. If you upload games created by another person, we’ll have to take them down.
Also, I’m going to go spam Zemlor now.